1. Field of the Invention
The present general inventive concept relates to a thin film transistor (TFT) array inspecting apparatus, and more particularly, to a TFT array inspecting apparatus which inspects a TFT array disposed at an inclined position so that TFT arrays having different sizes are continuously inspected, and allows an electron detecting unit to be disposed close to the TFT array so that secondary electron detecting performance is improved.
2. Description of the Related Art
A thin film transistor liquid crystal display (TFT-LCD), which is a type of a flat display panel device, is a device for displaying data using characteristics of liquid crystal, in which transmittancy of light is changed according to a voltage, is operable at a low voltage, and has a low power consumption rate, thereby being increasingly used in office automation (OA) equipment and household electric appliances.
Generally, the above TFT-LCD comprises a lower glass substrate on which arrays of TFTs serving as individual switching elements are installed, an upper glass substrate on which three color filters, i.e., red, green, and blue filters, are formed, a liquid crystal injected into a space between the lower glass substrate and the upper glass substrate, and a back light for supplying light emitted from an area below the lower glass substrate. The TFT-LCD varies a molecular structure according to electrical signals of the TFTs and a voltage applied to an LCD, and controls a degree of transmittance of the light. Then, the TFT-LCD causes the controlled light to pass through the three color filters, thus displaying desired color and image.
The above TFT-LCD is manufactured through an array manufacturing process in which the TFTs are formed, a cell manufacturing process in which the liquid crystal between a TFT array substrate (lower glass substrate) and a color filter substrate (upper glass substrate) is sealed, and a module manufacturing process in which an electric circuit for driving a TFT array substrate and a cell substrate is mounted.
After the TFT array is manufactured, it is inspected to determine whether or not the TFT array is defective. U.S. Pat. No. 6,075,245 discloses a TFT array inspecting apparatus.
The above TFT array inspecting apparatus comprises a CRT gun installed at an upper part of a vacuum chamber for emitting electron beam, a vacuum pump installed under the vacuum chamber for vacuuming an inside of the vacuum chamber, and an electric detector installed at one side of the vacuum chamber for detecting electrons emitted from a TFT array using the electron beam to inspect the TFT array disposed in the vacuum chamber.
The above conventional TFT array inspecting apparatus has a limitation in inspecting TFT arrays having various sizes in a single vacuum chamber. That is, a projection range of the CRT gun is set to a predetermined value according to the TFT array having a designated size, the TFT array inspecting apparatus cannot inspect TFT arrays having sizes larger than the set projection range of the CRT gun.
Accordingly, in order to inspect TFT arrays having sizes lager than the set projection range of the CRT gun, the projection range of the CRT gun is reset, and then the inside of the vacuum chamber is again vacuumed to a required vacuum degree. Thus, inspection of the TFT arrays having various sizes in a single chamber has a complicated procedure and requires a long period of time for preparing the complicated procedure.